Plastic glazing assemblies require a coating that can provide the assembly with acceptable performance properties, such as weatherability and interfacial adhesion with the underlying plastic substrate, as well as with any subsequently deposited abrasion resistant layer. Conventional methods of applying coating compositions include flow coating, dipping, spraying, spin coating, and curtain coating. All of these methods can apply a coating to a previously formed plastic sheet followed by the curing of the applied coating through a time consuming and energy inefficient process. A thermal curing method may require heating the coated glazing assembly for about 15 to 120 minutes at a temperature in excess of 100° C. The curing method may need to be performed multiple times depending upon whether the coating is comprised of multiple layers, such as a primer and topcoat. The time required for curing a conventional coating and the energy input necessary to achieve the required cure conditions substantially increases the manufacturing cost associated with a plastic glazing assembly. In addition, conventional coating methods lack high transfer efficiency rates, which when coupled with the presence of non-environmentally friendly solvents, require the manufacturer to further increase manufacturing costs by having to dispose of coating waste and scrapped parts, reduce air emissions, and provide for the installation and maintenance of a large coating line or facility.
Furthermore, many conventional coatings are either not compatible with the deposition of an abrasion resistant layer or are expensive due to the polymers and additives that make up their composition. More specifically, coatings that typically incorporate various inexpensive organic polymers in the coating matrix are not conducive to being a surface upon which a substantially inorganic abrasion resistant layer can effectively adhere. On the other hand, a coating comprising a silicon hard-coat (SHC), which is compatible with the deposition of an abrasion resistant layer, is many times more expensive than a conventional organic coating.
Therefore, there is a need in the industry to reduce the manufacturing costs associated with a plastic glazing assembly by reducing or eliminating the substantial costs of curing a conventional coating. There is also a need to insure that the coating applied to the plastic glazing assembly is compatible with the deposition of an abrasion resistant layer in order to provide the plastic glazing assembly with the necessary level of abrasion resistance required to function in an application over an extended life-time.